/*
 * Copyright (C) 2007 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package org.sufficientlysecure.keychain.util;


import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;

import androidx.annotation.NonNull;


public final class CountingOutputStream extends FilterOutputStream {

    private long count;

    /**
     * Wraps another output stream, counting the number of bytes written.
     *
     * @param out
     *         the output stream to be wrapped
     */
    public CountingOutputStream(@NonNull OutputStream out) {
        super(out);
    }

    /**
     * Returns the number of bytes written.
     */
    public long getCount() {
        return count;
    }

    @Override
    public void write(@NonNull byte[] b, int off, int len) throws IOException {
        out.write(b, off, len);
        count += len;
    }

    @Override
    public void write(int b) throws IOException {
        out.write(b);
        count++;
    }

    // Overriding close() because FilterOutputStream's close() method pre-JDK8 has bad behavior:
    // it silently ignores any exception thrown by flush(). Instead, just close the delegate stream.
    // It should flush itself if necessary.
    @Override
    public void close() throws IOException {
        out.close();
    }
}